Types of aggregates in a protein.. Disulphide linked? Hydrophobicity related? - Conditions that can make or break them? (Dec/25/2006 )

Hiya!
I'm looking for types of aggregates that can be formed in proteins.. say, in a purified protein preparation.. what kind of aggregation may happen?
Disulphide linked? Hydrophobicity related? What else?

Waht are the conditions that can:
1. Induce formation of these in a preparation.. say temperature stress, some chemical.. each kind of aggregate spearately
2. Break them when present.. say DTT-BME, Heat, some chemical.. each kind of aggregate spearately

Plsss lemme know quick.. Thanks much:)

---

ok, what i know is that proteins exposed to high salt concentrations tend to form aggregates due to hydrophobicity....
and for disulfide bonds, reducing agents are used

---

I think it is really complicated. maby noone knowns why excaly and how proteins aggregate. some hydrophobic residues may play a role. but what do you want to do? make a protein aggregate and then make it soluble again?

---

Yess.. I want to make protein aggregates and make them soluble again.. to know their behavior. And then compare this to the naturally occuring aggregates in a few of my samples.

---

that is very interesting. actually after trying to express my protein in E-coli and getting only inclusion bodies i became interested with aggregation myself. in my case i think cleavage causes aggregation. it is only my hypothesis of course. but it seems that the hydrophilic end of the protein is cleaved off (shorter protein on the PAGE) and it becomes more hydrophobic and missfolds then aggregates. try to cleave some protein maybe

---

if I had this work to do, I would start to find a pH (between pH6.5 and pH7.8, no harsh) where I observe aggregation; it should work by protonation; and deprotonation should revert aggregation; it works for some cytoplasm proteins

optimum performance is to look in cells f.i. by GFP;

---